A cheating doctor and his mother accused of poisoning his wife after she discovered he was having an affair have been seized by police.
Pilates instructor Larissa Talle Leoncio Rodrigues, 37, had told friends she was planning to divorce her surgeon husband after finding out about his lover.
But she died in agony at the couple's apartment in Ribeirao Preto, in the Brazilian state of Sao Paulo, after being slipped a lethal dose of a powerful insecticide by her mother-in-law, say police.
Professor Larissa Rodrigues poses with husband in undated photo. She died in Ribeirao Preto, Brazil. Note: Private photo taken from social media. (Newsflash/NX)
Larissa's husband, Luiz Antonio Garnica, 38, and his 64-year-old mother, Elizabete Arrabaca, were arrested on 6th May after toxicology tests revealed Larissa had been poisoned.
Friends told police she had talked of her plan to divorce Garnica after discovering his 18-month romance with a 26-year-old student.
Local media reports say Larissa had confronted the medic after finding "incriminating items" in his car.
Professor Larissa Rodrigues poses in undated photo. She died in Ribeirao Preto, Brazil. Note: Private photo taken from social media. (Newsflash/NX)
On the morning of her death on 22nd March, Garnica told police he'd found her unresponsive in the bathroom and had attempted to revive her after calling for help.
But suspicious paramedics noted that her stiffening body from rigor mortis meant she had been dead for some time.
They also told police that the apartment reeked and a strong smell of cleaning products.
Police told local media: "His involvement was quite evident to us by the way he found Larissa.
Professor Larissa Rodrigues poses with husband in undated photo. She died in Ribeirao Preto, Brazil. Note: Private photo taken from social media. (Newsflash/NX)
"She was already in rigor mortis and he was trying to clean the apartment as if he were trying to destroy the evidence for the forensic expert."
Prosecutors believe Larissa died after eating grapes laced with the deadly pesticide 'chumbinho', a local nickname for an agricultural poison often used in homicides.
Just two weeks before she was found dead, say police, her mother-in-law, the last person to see Larissa alive, had been trying to buy the powerful pesticide.
City police chief Fernando Bravo revealed: "We managed to find a witness who reported that her mother-in-law was looking for chumbinho to buy, approximately 15 days before her death.
Professor Larissa Rodrigues poses with husband in undated photo. She died in Ribeirao Preto, Brazil. Note: Private photo taken from social media. (Newsflash/NX)
"She called a friend who is a farmer to find out if he had this substance on his farm.
"When her friend said no, she asked for a recommendation of where to buy it, but no one provided it or indicated it.
"So this gave us certainty that she, along with her son, killed Larissa."
The couple had been together for 18 years, and ironically, Larissa had reportedly confided in her mother-in-law about her husband's infidelity.
Garnica's lawyer, Julio Mossin, says the doctor denies any wrongdoing.
The investigation continues.
(MJ Leidig/newsX)